The evidence-based medical treatment of heart failure (HF) with reduced left ventricular function (HFrEF) includes angiotensin-converting-enzyme inhibitors (ACEI) or angiotensin-receptor blockers (ARB) as an alternative for patients who do not tolerate an ACEI, beta-blockers (BB), and mineralocorticoid-receptor antagonists (MRA). This evidence concerns the gene NR3C2 and heart failure.